1. Field of Invention
The present invention relates to a method of printing geometric figures, and more particularly to a method of printing geometric figures in which coordinates are recombined to speed up geometric figures layout.
2. Related Art
As the information technology rapidly develops, the world today has been well computerized and the interconnected network has also spread over. Printing devices cannot be omitted in data layout, although the cycle periods of the computer-related products are shorter and shorter. Under the intense competition in the printer market, the printing speed and the print quality are of interest for future development.
In printing, a polygonal figure or text constructed of scan lines or poly scan lines needs a plurality of horizontally linear lines or rectangular lines.
In FIG. 1, a conventional method of drawing scan lines draws the lines one by one from top to bottom or in the reverse direction, each line being next to the other.
If the geometric figure is constructed of four sets of scan lines which are respectively indicated in two-dimensional coordinates:                First set: (0,0)-(10,0); (20,0)-(30,0); (40,0)-(50,0)        Second set: (0,1)-(10,1); (20,1)-(30,1); (40,1)-(50,1)        Third set: (0,2)-(10,2); (20,2)-(30,2); (40,2)-(50,2)        Fourth set: (0,3)-(10,3); (20,3)-(30,3); (40,3)-(50,3)        Command format: PE=<X1,Y1, (X2-X1), (Y2-Y1);        Output command: PE=<0,0,10,0;                    PE=<20,0,10,0;            PE=<40,0,10,0;            PE=<0,1,10,1;            PE=<20,1,10,1;            PE=<40,1,10,1;            PE=<0,2,10,2;            PE=<20,2,10,2;            PE=<40,2,10,2;            PE=<0,3,10,3;            PE=<20,3,10,3;            PE=<40,3,10,3;                        The command length=4 bytes;        The coordinate length of each set=4 bytes;        
Therefore, the estimated command length which is needed=(4-byte commands+4 bytes*2 sets of coordinates)*12 sets of commands=144 bytes.
As shown in FIG. 2, the conventional method of drawing the poly scan lines draws one row of rectangular figures each time from top to bottom or from bottom to top. The adjacent rectangular figures are next to each other or partially superimpose each other.
As illustrated, it is assumed that the geometric figure is constructed of three sets of poly scan lines, which respectively indicate two-dimensional coordinates:                First set:        {(0,0),(10,0),(10,10),(0,10)},{(40,0),(50,0),(50,10),(40,10)}        Second set:        {(0,10),(20,10),(20,20),(0,20)}, {(10,10),(20,10),(20,20),(10,20)}, {(30,10),(40,10),(40,20),(30,20)}, {(40,10),(50,10),(50,20),(40,20)}        Third set:        {(0,20),(10,20),(10,30),(0,30)}, {(40,20),(50,20),(50,30),(4,30)}        Command format:        PE=<X1,Y1, (X2-X1), (Y2-Y1), . . . (Xn-Xn−1, Yn-Yn−1), (X1-Xn,Y1-Yn);        Output command: PE=<0,0,10,0,0,10,−10,0,0,−10;                    PE=<40,0,10,0,0,10,−10,0,0,−10;            PE=<0,10,10,0,0,0,10,−10,0,0,−10;            PE=<10,10,10,0,0,10,−10,0,0,−10;            PE=<30,10,10,0,0,0,10,−10,0,0,−10;            PE=<40,10,10,0,0,10,−10,0,0,−10;            PE=<0,10,10,0,0,0,10,−10,0,0,−10;            PE=<40,10,10,0,0,0,10,−10,0,0,−10;                        The command length=4 bytes;        The coordinate length of each coordinate=4 bytes;        Therefore, the estimated command length=(4-byte command+4 bytes*5 coordinates)*8 sets of commands=192 bytes∘        
The above-mentioned method needs to output a lot of commands and coordinates. When these data are transmitted to a printer, the printing operation takes time and some geometric figures repeat or superimpose each other, which slows down the printing speed.